Demonstrators remain behind an improvised barricade during clashes with riot police within protests in Monimbo neighborhood in Masaya. (Photo: Reuters)

At least five people died in the flashpoint city of Masaya in Nicaragua during a night of clashes between police and anti-government protesters, a rights group said Monday, with residents describing scenes of terror in the streets.

The city saw running battles all weekend between residents armed with home-made mortars and slingshots who are trying to repel riot police and what they say are paramilitary forces loyal to President Daniel Ortega.

More than 100 people have died in the violence sweeping Nicaragua since protests erupted on April 18 against Ortega, the man who has dominated the Central American country's politics for four decades.

The new death toll in Masaya, a city of just over 100,000 people next door to the capital Managua, counted victims killed between Sunday night and Monday morning, according to Alvaro Leiva, head of the Nicaraguan Association for the Protection of Human Rights (ANPDH).

The agency has identified just one of the victims so far, a 23-year-old teacher named Carlos Lopez, who was killed by a bullet in the torso -- indicating "he was executed, no doubt, by snipers," Leiva said.

"There is a profound violation of human rights" in Masaya, said Leiva.

- 'Practically an invasion' -

Catholic priest Augusto Gutierrez, whose parish is in the city's Monimbo neighborhood, said the security forces had launched a "generalized attack."

"It was practically an invasion of the city with heavy armaments. There were bursts of (automatic weapons) fire," he told AFP.

An injured demonstrator is helped after being shot during clashes against riot police, in Monimbo neighborhood in Masaya. (Photo: Reuters)

"I don't know anything about war, but there were multiple times when they fired in rapid succession: ta-ta-ta, in bursts."

He said the attackers were riot police and plainclothes groups who entered the city in pick-up trucks, their guns blazing.

Multiple witnesses told him stories of summary executions by the police, he said.

One man was forced to kneel down before a police officer.

"If you're going to kill me, then kill me," he shouted to her, according to the priest, who said the officer then shot him.

Another young man of 15 "begged for his life," but was also shot dead, he said.

- Under siege -

Residents in Masaya have constructed barricades throughout the city with cobblestones, furniture, sheet metal and virtually anything else available to try to keep out Ortega's security forces, which they accuse of pillaging the city of 100,000 people.

The government blames criminals for the pillaging, and says it sent in riot police at the request of small-business owners.

A demonstrator runs carrying a home-made mortar during protests in Monimbo neighborhood in Masaya, a city that neighbors Managua. (Photo: Reuters)

Protesters have captured a number of police officers during the clashes, while police have arrested several demonstrators, many of whom say they have been badly beaten while in custody.

At least 113 people have been killed in the nearly eight weeks of violence, according to another rights group, the Nicaraguan Center for Human Rights (CENIDH) -- though it had not yet confirmed the latest deaths reported in Masaya.

The city's police chief Ramon Avellan meanwhile reported the death of a 22-year-old police officer in Masaya, allegedly killed when demonstrators attacked the city's police station.

It was unclear whether that death was included in the toll given by the ANPDH.

- Virtual curfew -

In Managua there is a virtual curfew in place after dark, with motorcycle gangs terrorizing those who venture out, according to the CENIDH.

The wave of protests against Ortega and his ruling party -- the Sandinista National Liberation Front -- erupted on April 18 and quickly turned violent.

A demonstrator stands behind a barricade during protests in Monimbo neighborhood in Masaya. (Photo: Reuters)

The brutal crackdown on what started as relatively small protests against cuts to pension benefits have fueled demands for the ouster of Ortega and his wife and vice president, Rosario Murillo.

Ortega, whose third consecutive term is due to end in 2022, accuses right-wing opposition groups of conspiring to "terrorize" the country.